[Morphological characteristics of recurrent papillary thyroid carcinoma]

Papillary thyroid carcinoma is generally characterized by a favorable prognosis in patients after timely and adequate treatment. However, local tumor growth recurrences and regional and distant metastases may occur in 5-20% of cases posttreatment.

To comparatively analyze the morphology and cellular composition of papillary thyroid carcinoma in two patient groups with comparable clinical and morphological characteristics, but different in the long-term results of treatment.

Histological specimens from 17 papillary thyroid carcinoma cases with recurrent tumor growth after treatment and resurgery (an experimental group) and 18 control cases without recurrences were selected from the database of the Chernobyl bank. The morphological features of primary tumors were studied in both groups; the morphology of recurrent tumors was also investigated in the experimental group.

The higher incidence of tumors with papillary structure and a focal component from high-columnar, clear, and oxyphilic tumor cells was found in a group with a poor prognosis (a local relapse and metastases in the regional lymph nodes after thyroidectomy, hormonal and radioiodine therapy.

The found morphological features of recurrent papillary thyroid carcinoma may serve as a starting point for further establishing criteria for tumor resistance to radioiodine therapy and for substantiating indications for other high-technology treatments, including targeted therapy.